The Force required to assemble (press fit) cylindrical parts
depends on the allowance or clearance between the cylindrical parts for the fit,
area of the positioned and fitted surfaces, the pressure increasing in
proportion to the distance that the shaft feature is forced in.

The approximate ultimate pressure in tons can be determined by
the following formula:

P = (A x a x F)/2

Where:

P= Ultimate pressure required, in tonsA = Area of surface in contact between the shaft and hole feature
a = Total allowance or actual material interfering between the shaft and hole
feature in inches; (pin diameter - bore diameter)
F = Pressure factor

Assumptions:

Diameter of the hub (feature which force is applied to) is twice the diameter of the
pin which is pressed into the bore)